Put the potatoes in a large pot and add just enough water to cover them. Bring to a boil and cook until fork-tender, about 15 minutes.
Drain and put potatoes back to the pot on the stove top with the heat turned off. This helps any excess water evaporate.
Add butter and warm until butter is melted, then mash roughly. Add plant-based milk or cream, salt, pepper to taste and mash until smooth and creamy. (Please do not add too much milk, because this can make the potatoes soupy.)
For the Gravy (Make this while the potatoes cook):
Heat the vegan butter (or oil) in a large pan over medium heat. Sauté the onions until translucent and browned, about 4-5 minutes. Add garlic and sauté for 1 minute longer.
Add mushrooms and fry until lightly browned, about 5 minutes. Season with salt and pepper to taste.
Pour in vegetable broth, soy sauce, and plant-based cream.
In a small cup, add cornstarch to a little water and stir to dissolve. Stir in the sauce and bring to a simmer. Cook for 5-7 minutes, until gravy has thickened to desired consistency. Add nutritional yeast flakes (optional) and more salt and pepper if needed.
Top your mashed potatoes with mushroom gravy, fresh herbs and toasted pine nuts (optional). Serve immediately.
I used regular white potatoes and sweet potatoes for this recipe, but you could also use any other variety of creamy potatoes or vegetables.
Nutrition is calculated automatically and should be used as estimate.